摘要
使用直流电阻率法进行黄土水分监测时,黄土介质中的容性成分会影响结果的准确性。该文以宜川地区黄土为研究对象,基于复电阻率试验和土水特征测定,获取了非饱和黄土基质吸力与复电阻率参数的关系,揭示了其频谱特性变化规律,推导了黄土饱和度与复电阻率公式。研究结果表明:激励频率与复电阻率的幅值和相位呈负相关关系,在频率小于1 000 Hz时黄土的复电阻率的幅值和相位波动较大,超过1 000 Hz时会逐渐趋于稳定;随着基质吸力的升高,黄土的幅值、实部电阻率和虚部电阻率也逐渐增大,其相关性受通电频率的大小影响;黄土电容量与介电常数随基质吸力的升高逐渐减小;利用实部电阻率和虚部电阻率建立了黄土饱和度复电阻率模型,模型可用于黄土水分变化的监测。研究结果为利用黄土的频散特性进行黄土地质灾害监测提供了新的方法和思路。
The accuracy of the results is influenced by capacitive components.This paper focuses on loess in the Yichuan region and establishes the relationship between unsaturated loess matrix suction and complex resistivity parameters based on complex resistivity tests and soil-water characteristic determinations.It reveals the variation patterns of their spectral characteristics and derives formulas for loess saturation degree and complex resistivity.The research results indicate that the excitation frequency is negatively correlated with the amplitude and phase of complex resistivity.When the frequency is less than 1000 Hz,the amplitude and phase of loess complex resistivity fluctuate significantly,stabilizing gradually after it exceeds 1000 Hz.With the increase of matrix suction,the amplitude,real part resistivity,and imaginary part resistivity of loess gradually increase,with their correlation influenced by the applied frequency.Loess capacitance and dielectric constant decrease with the increasing matrix suction.A loess saturation degree-complex resistivity model is established using the real part resistivity and imaginary part resistivity,and the model can be used for monitoring moisture changes in loess.The research results provide new methods and perspectives for utilizing the frequency dispersion characteristics of loess in geological disaster monitoring.
作者
李鑫
谷天峰
崔博
LI Xin;GU Tianfeng;CUI Bo(State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China)
出处
《西北大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第1期42-52,共11页
Journal of Northwest University（Natural Science Edition）
基金
国家自然科学基金专项项目(42041006)
国家重大科研仪器研制项目(42027806)。
关键词
黄土
复电阻率法
频谱特性
基质吸力
饱和度复电阻率模型
loess
complex resistivity
spectral characteristics
matric suction
saturation-complex resistivity model
